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According to the study on the practical Chaolianxijiang bridge, the stress state of cable-pylon anchorage zone of cable-stayed bridge under two kinds of prestressed arrangements (that is, U-shaped arrangement and parallel arrangement) were calculated and compared. The results suggested that parallel prestressed arrangement could avoid the difficulty caused by other arrangements in the construction. Parallel prestressed arrangement with clear concept, simple structure, clear stress and small amount of work is suitable for the thick walled cable-pylon.

Because the flow of river bridge was not suitable for bearing existing vehicle load, it is needed to be dismantled, and a new bridge will build on the original site. The overall construction plan is using double bridge girder erection machines to remove box girder and the suspended beam of the main bridge. In order to guarantee the security of assembling the bridge girder erection machines and lifting the beam, we did some research in assembling technology, using the finite element software MIDAS to establish model of sling equipment, and analyses whether the sling equipment can bear the design load . With the purpose of ensuring the stability and safety of the suspended beam in the process of hoisting, the suitable order of hoisting suspended beam and risk control of slipping the suspended beam were analyzed. For purpose of guaranteeing the stability of the hoisting box girder, the construction team designed the stabilization system. Due to the complexity of the stress of the girder in the demolition process, we use the finite element software ANSYS to establish the model of e box girder in the process of hoisting, and analyze its stress and deformation. According to the practical engineering, we draw a conclusion: the box girder, suspended beam remained stable in the process of hoisting, and their internal forces conform to the requirements of the specification. The overall construction plan can provide a reference for other similar projects.

A 10DOF composite beam element was developed, which had taken the interface slip effect and geometric nonlinearity into consideration. The method to obtain structural response gradients of composite beam was analyzed, meanwhile the reliability index was achieved by using the FORM method and on this basis, and the sensitivity of random variable parameters could be finished. At last the control of target elevation was took as state performance function, the sensitivity analysis of random variable parameters which might have an effect on the elevation control reliability was effectively completed, and some useful conclusions which were be beneficial to construction control of composite beam cable-stayed bridge obtained.

Bridge jacking technology is a new technology in the field of old bridge reconstruction. Based on the case of Beijiang River Bridge jacking of Fokai highway extension engineering, the paper designs steel hoop as jacking force platform. By using ANSYS software, it makes finite element analysis and calculation as well as compares with the experimental data to check the reliability of models. In addition, the paper puts forward the optimization methods of steel hoop based on the analysis of the results. At last, it achieves the objective of saving materials and simplifying installation and use as well as provides guidance for the similar engineering.

The paper aims to do the reliability analysis by the Kriging model. Its excellent approximating capability is taken into consideration, which is superior to traditional response surface method. An improved response surface method has been proposed based on the Kriging model. The seismic response of structure is characterized by nonlinear and complexity, more difficulties in the reliability analysis have been found as well. Compared to other methods of reliability analysis, the response surface method is regarded as an effective way to solve such problems. Thus the improved response surface method based on the Kriging is utilized to analyze the structural first excursion dynamic reliability problem under random seismic excitation. Meanwhile, the influence on the reliability due to the randomness of structural parameters is analyzed.

In this paper, the construction technology for main pylon of cable-stayed bridge is researched through test of full-scale model of anchorage zone of pylon of Guangzhou Bridge. Stress distribution and deformation condition of model under prestressed tendons and cable force are analyzed. Numerical simulation on this anchorage zone model is carried out. By comparing FEM results to the test results, some important conclusions are drawn out and give some advices to the optimum design of the bridge pylon. Parts of the achievements have been applied to actual bridge work and obtained successful engineering experience.

In this paper, a continuous beam arch bridge Dukeng bridge was introduced. Its construction process and its construction monitoring were discussed. In the construction process, the elevations of the box girders measured were closer to the values theoretical calculated. Though construction monitoring, although there were some construction errors, they can be timely adjusted and rectified and the main beam was ensure to smoothly closure.

In this paper, first order reliability method (FORM) is generalized to the seismic reliability analysis of long-span bridges and the first excursion probability of a single tower cable-stayed bridge is studied. The seismic motivation is firstly dispersed as a series of random variables. Then the cross velocities on the dispersed time points can be obtained by solving the motivation of the design checking points with FORM. The upper bound of first excursion probability is also obtained by integrating the cross velocities at different time. The results show that the seismic reliability analysis method based on the FORM is feasible and effective to solve the first excursion probability problem. The single tower cable-stayed bridge studied in this paper has a higher reliability under strong seismic.

During the construction stage of the bridge, the elevation control could be influenced by many random factors, the allowable deviation of elevation control could be obviously influenced by human factors, and the threshold of controlled elevation depends on both the requirement of structural design and the subjective factors of controller, which is characterized by strong fuzziness. A composite beam cable-stayed bridge is composed of complex structure members which have the characteristic of complexity in structure analysis, strong randomness in parameters, and difficulty in construction control. Therefore, it couldn't be better to set the composite beam cable-stayed bridge as the target for fuzzy random structure analysis. The Direct Differentiation Method was used to obtain structural response gradients of composite beam, and it was combined with the method of transforming fuzzy membership function equivalently to the random density function. Finally, based on a real bridge construction process, the fuzzy random reliability analysis of the bridge elevation control was finished availably.